A passenger on a delayed flight tried this out. He checked the weather on his iPhone, noticed the weather was clearing up, told the flight attendant about his findings, the flight attendant relays the message to the captain. The iPhone owner probably had a brief feeling of "this gadget saved the day", just like the commercial Apple advertises on TV.
His "iPhone moment" would soon end very different than the commercial he saw on TV.
The pilot says over the PA system, “If the passenger with the iPhone would be kind enough to use it to check the weather at our alternate, calculate our fuel burn due to being rerouted around the storms, call the dispatcher to arrange our release, and then make a phone call to the nearest Air Traffic Control center to arrange our timely departure amongst the other aircraft carrying passengers with IPhones, then we will be more than happy to depart. Please ring your call button to advise the Flight Attendant and your fellow passengers when you deem it ready and responsible for this multi-million dollar aircraft and its passengers to safely leave.”